Area Forecast Discussion
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FXUS61 KBTV 272047
Area Forecast Discussion
National Weather Service Burlington VT
347 PM EST Mon Feb 27 2017
Westerly flow over our area is south of a weak frontal system in
Quebec. It will bring partly skies south to mostly cloudy skies
in the north along with breezy and mild conditions this
afternoon. Weak high pressure tonight will yield fair weather
and seasonably mild temperatures tonight. Periods of rain with
well above normal temps return late Tuesday into Wednesday as a
slow moving front moves across the region. This could produce
more rises on our above normal stream levels. Much cooler air
arrives by the end of the week...along with chances for mainly
mountain snow showers.
.NEAR TERM /THROUGH TUESDAY/...
As of 347 PM EST Monday...A weak ridge of high pressure moves
across the region overnight and as the winds turn calm expect a
very shallow inversion to develop as radiational cooling will
drop our overnight lows into the 20s. How cold it gets will
depend on the how clear the skies get but looking more clearing
north than south.
On Tuesday...Warm advection gets underway with increasing
clouds and a chance of light rain showers mainly mid afternoon
onward from SW to NE. 925 mb temps rise to 1 to 3 deg C by 18Z
which should give us high temps in the mid 40s to lower 50s.
.SHORT TERM /TUESDAY NIGHT THROUGH WEDNESDAY/...
As of 338 AM EST Monday...West to southwest flow aloft aloft
will develop over the area through the entire period. This will
lead to temperature and moisture advection and we will once
again see above normal temperatures through the period. Highs on
Tuesday will be in the mid 40s to lower 50s and in the mid 50s
to lower 60s on Wednesday. With the temperatures on Wednesday...
there will likely be some more record highs set. Of note will
be the lows Tuesday night...which will be above freezing. So we
will once again have an extended period of conditions favorable
for more ice breakup in rivers plus new snowmelt. Showers will
be off an on during the period...especially Tuesday night into
Wednesday. Standardized anomalies for precipitable water will be
three times higher than normal...so will need to keep an eye on
potential precipitation amounts. At this time we could be
looking at a half inch to three quarters of an inch in the
Tuesday through Wednesday night time period.
.LONG TERM /WEDNESDAY NIGHT THROUGH SUNDAY/...
As of 338 AM EST Monday...Upper trough will be moving across
the area Wednesday night into Thursday and will be bringing an
end to the precipitation from west to east. Temperatures will
also be falling and we will be trending toward below normal
temperatures as we head to the weekend with northwest flow aloft
becoming established over the region. Drier air will also be
moving in and precipitation chances will be pretty small as a
result with temperatures cold enough for precipitation to be in
the form of snow showers.
.AVIATION /20Z Monday THROUGH Saturday/...
Through 18Z Tuesday...A weak ridge of high pressure will pull
east of the region during the morning hours today. Expect VFR
conditions to prevail through TAF period. Only aviation concern
will be the gusty pressure gradient winds across the region
today. With steep lapse rates and decent mixing expect gusts of
20-30kts at most TAF sites through the afternoon. The low level
jet at 850mb will likely cause some issues with wind shear and
low level turbulence especially over northern New York, but with
the gusts mentioned in the TAF`s I opted to not include any
mention of LLWS in the TAFs.
Outlook 12Z Tuesday through Saturday...
18Z Tuesday - 06Z Thursday...Scattered/numerous rain showers
with variable cigs from VFR to IFR before low pressure and cold
front crosses the region Wed evening.
06Z Thursday 12Z Saturday...Becoming Mainly VFR but ocnl snow
showers/flurries and MVFR/IFR conditions.
12z Saturday onward...Mainly VFR under high pressure.
As of 100 PM EST Monday...The last river in flood is the Barton
River in Coventry. The river level are receding and expect this
river to go back below flood stage this evening.
We continue to watch Tuesday eve through Wed time period
closely for the potential for additional river rises associated
with several rounds of showers. This expected rainfall along
with much above normal temperatures will result in additional
snow melt and the potential for river rises...especially given
the already high levels. The good news is that most river ice is
gone and our areal coverage of deep snow pack is much less than
previous event...resulting in less runoff potential. We will
continue to monitor for potential impacts.
We could see some records broken on Wednesday based on our
forecast high temperatures. Current records for March 1st are
Burlington - 59 set in 1954
Montpelier - 53 set in 1991
St. Johnsbury - 58 set in 1954
Massena - 49 set in 1954